Portable tree-felling and logcutting circle saw



April 14, 1953 A. w. MALL 2,634,770

PORTABLE TREE-FELLING AND LOG-CUTTING CIRCLE SAW Filed June 1, 1948 5Sheets-Sheet l A. W. MALL April 14, 1953 PORTABLE TREE-FELLING ANDLOG-CUTTING CIRCLE SAW Filed June l, 1948 5 Sheets-Sheet 5 April 14,1953 A. w. MALL PORTABLE TREE-FELLING AND LOG-CUTTING CIRCLE SAW FiledJune 1, 1948 5 Sheets-Sheet 4 M NW, \N w April 14, 1953 A. w. MALL2,634,770

PORTABLE TREE-FELLING AND LOG-CUTTING CIRCLE SAW Filed June 1, 1948 5Sheet sr-Sheet 5 E l/ix;

w gw Patented Apr. 14, 1953 PORTABLE TREE-FELLING AND LOG- CUTTINGCIRCLE SAW Arthur W. Mall, Flossmoor, Ill., assignor to Mall ToolCompany, Chicago, 111., a. corporation of Illinois Application June 1,1948, Serial No. 30,357

4 Claims.

The present invention relates to a portable cir- 'cular saw of the typethat may be used for felling trees and cutting the trees and logs intoshorter lengths. The saw comprises an elongated frame mounted on a pairof wheels. The wheels may be disposed substantially midway between theends of the frame and a power unit is mounted at one end of the frameWhereas a circular saw is disposed at the other end. The saw bladertates about an axis that is disposed at right angles to the long axisof the frame. The entire unit is suited for operation by one person whostands at the motor end of the device and the cutting operation iseffected by simply rolling the entire unit on its wheels in a mannersimilar to a wheelbarrow to feed the rotating saw blade into the Wood.

One object of the invention is to provide such a unit wherein all of thedrive mechanism is completely enclosed, thereby eliminating as much aspossible danger of injury to the person using the saw.

The present device is intended for use in felling trees and clearingland of underbrush and the like and for this purpose the saw rotates ina substantial horizontal plane. For cutting trees and logs into shorterlengths, however, it may be I necessary to have the saw blade rotate insome other plane, either vertical or perhaps intermediate.

Another object of the invention is to provide a saw where changes ofposition of the blade can be brought about by the operator in a simplemanner without requiring his changing his position from that requiredfor normal operation of the device.

The foregoing constitute some of the principal objects and advantages ofthe present invention, others of which will become apparent from thefollowing description and the drawings, in which Fig. l is a sideelevational view of the complete :saw unit embodying the presentinvention;

Fig. 2 is a plan View of the unit shown in Fig, l, the saw blade beingillustrated in two positions;

Fig. 3 is a front end view of the saw, the saw blade being illustratedin solid lines in a horizontal position to rotate about a vertical axisand in broken lines in each of two other positions;

Fig. 4 is an enlarged, transverse sectional view through the saw unit,the view being taken on the line 5-4 of Fig. 5;

Fig. 5 is an enlarged, fragmentary, longitudinal sectional view throughthe saw, the view being taken along the line 55 of Fig. 2;

Fig. 6 is a transverse sectional view taken through the clutch portionof the saw unit, the View being taken on the line 6-6 of Fig. '7;

Fig. 7 is an enlarged, fragmentary, longitudinal sectional view throughthe saw unit, the view being taken along the line 1-4 of Fig. 2; and

Fig. 8 is a more or less diagrammatic view illustrating the present sawin position for operation to cut a tree on the side of a hill.

For purposes of illustration a single embodiment of the presentinvention has been shown and will be described hereinafter. It isrecognized, however, that many modifications may be made in the form ofthe invention shown without departing from the intended scope and spiritof the invention,

Referring now to the drawings and particularly to Figs. 1, 2 and 3, thesaw unit comprises a frame generally indicated at [0 that includes apair of legs I l on each of which is mounted one of a pair of wheels 12.The frame It is elongated and at one end is provided with an engine ormotor l3 and at the other end with an arm [4 that is disposedsubstantially at right angles to the axis of the elongated frame it].Disposed at the free end of the arm H3 is a circular saw blade 54.

The frame [0 more specifically comprises a sleeve member IE to which thelegs H are rigidly secured by means of bolts or the like ll. Mounted inthis sleeve l6 and extending rearwardly therefrom is an elongated tubeI8 that is rigidly secured to the sleeve by means of screws, one ofwhich is shown at l9 in Fig. 5. A coupling member 28 is fixed by meansof screws 2| onto the free end of this tube [8 and the engine or motorunit l3 (Fig. 2) is fixed to the free end of this coupling member 20 bymeans of screws 22 (Fig. 5).

The engine or motor unit It includes the prim mover or engine 23 of anysuitable type having an engine drive shaft 24 (Fig. '7) on the end ofwhich may be disposed a centrifugal clutch generally indicated at 25.This engine 23 forms no part of the present invention and, therefore, itis deemed unnecessary to describe in detail the various parts of theengine and the engine drive.

Mounted in rotation with the coupling member 20 is a stub shaft 26 thatoperates in bearings 21 and on one end of this shaft 26 is a cup shapedclutch element 28 forming the driven member of the centrifugal member 25(see Figs. 5 and 7). The centrifugal clutch 25 further comprises acentrifugal portion 29 that is mounted on the end of shaft 24 and servesto cooperate with the cup shaped clutch element 28 when the speed ofrotation of shaft 24 reaches a predetermined R. P. M. to drive stubshaft 26.

For purposes of illustration this centrifugal portion 29 of the clutch25 comprises generally clutch shoes 30 (Fig. 6) that are pivoted as at3! to an arm 32 which in turn is pivoted about an axis 33 that isdisposed at the center line of the shaft 24. The shoes 30 are normallyheld in collapsed condition by means of springs 34. The outer face ofeach of the shoes 30 is provided with a lining material of fabric or thelike that will provide a relatively high coefficient of friction. As thespeed of rotation of the shaft 24 reaches a predetermined R. P. M. theclutch shoes 30 are brought into engagement with the inner annular faceof the cup shaped clutch element 28 to create a positive drive from thshaft 24 through the clutch 25 to the shaft 26. Shaft 24 is drivendirectly from the engine 23.

As best shown in Figs. 1 to 3 inclusive a pair of rearwardly extendinghandle bars 35 is fixed to the engine 23 and they are so spaced thatthey can be conveniently grasped by the operator of the saw unit. Theengine 23 may be gasoline driven and provided with a throttle that isoperated by a finger lever 36 that is disposed on one of the handle bars35.

Mounted in the forward end of the sleeve member I6 and projectingforwardly therefrom is an elongated tube 31 on the free end of which ismounted a cutter assembly member 38. The sleeve 31 is telescoped overthe end of tube l8 and is adapted to rotate about the tube I8 and insleeve [6. The cutter assembly member 38 s fixed to rotate with the tube31 by suitable screws, one of which is shown at 39 in Fig. 5. Mounted inthe upper portion of the cutter assembly member 38 is a horizontallydisposed stub shaft 40 that is journalled in suitable spaced bearings41. One end 40a. of this shaft 40 projects into the end of tube 31 andmounted on this projecting end 40a is a rotatable shaft 42 that isdisposed inside the tubes and 31. The other end of shaft 42 is mountedon the end 26a of stub shaft 26 that is disposed in the coupling member20. Thus the stub shaft 40 is driven from the engine 23 through stubshaft 26 and shaft 42.

The cutter assembly member 38 is provided with a downwardly disposedtubular portion 43 in which is mounted a rotatable shaft 44 that issuitably journalled at opposite ends as indicated at 45 and 46. A gearbox portion 41 is provided at the upper end of the tubular portion 43 ofthe cutter assembly member 38 and the shaft 44 projects into this gearbox portion. A gear 48 is mounted on the upper end of the shaft 44 andis fixed in place by means of a suitable nut 49 threaded onto the end ofthe shaft and is adapted to mesh with a pinion 50 that is mounted on theend of stub shaft 40. The gear box member 41 is provided with aremovable cover that is secured in place by suitable screws 52. A web 53serves as a gusset for reinforcing the cutter assembly member 38.

The shaft 44 pro ects below the lower edge of the cutter assembly member38 and mounted on this free end of the shaft 44 is a cutter or circularsaw blade 54 that is held in place by inner and outer plates 55 that areclamped together by a nut 56 that is threaded onto the end of the shaft.

Thus there is provided a saw unit that is adapted to support a circularsaw blade 54 that is rotated with shaft 44 through suitable gears 48 and50 from an engine drive that includes driven shafts 26, 42 and 40. Asshown in Fig. 5 the circular saw blade 54 lies in a horizontal plane andin order to fell a tree or the like, the person operating the sawassumes a position behind the handle bars 35 (Figs. 1 and 2) and pushesthe entire unit on wheels I2 so as to feed the rotating saw blade 54into the tree.

For many purposes it is desirable that the saw blade 54 be disposed in avertical plane or in some plane other than the horizontal planeillustrated in Figs. 1, v2 and 5. in solid lines. This can very readilybe accomplished with the saw unit forming the subject matter of thepresent invention by merely causing the entire tube 3! together with thesaw assembly unit 38 to be rotated in the sleeve [6 until the saw bladeis disposed in the desired position. It is, of course, necessary to lockthe cutter assembly member 38 when the blade has reached its desiredposition and for this purpose an indexing and locking assembly generallyindicated at 51 in Fig. 5 is utilized.

This assembly includes an indexing ring 58 shown in Figs. 4 and 5 thatis mounted concentrically about the tube 31 and is fixed with respect tothis tube. This indexing ring 53 is notched as at 59 about its peripheryand for purposes of illustration these notches are disposed at thirtydegree intervals about the entire periphery. Surrounding this indexingring 58 is an indexing pin assembly generally indicated at 60 thatincludes a clamping ring Gila at the under side of which is a downwardlyprojectin pin housing 6l' in which is mounted an indexin pin generallyindicated at 62. This pin 62 includes a pin head portion 63 having adownwardl extending shank 64 of smaller diameter than the head portion63. A cap 65 is threaded onto the lower end of the pin housing El and anipple 66 is held between the cap 65 and the end of the housing '61. Acompression spring 6'! is mounted concentrically about the shank 54 ofpin 62 and is seated between the pin head 53 and the upper end of thenipple 66. The pin 62 is adapted to slide up and down in the indexinghousing 6! but is constantly urged in its upper position shown in Fig. 4by the compression spring 5 The head portion 63 of the indexing pin 62is provided with an outwardly projecting tooth or lug 68 that is adaptedto project into any of the notches 59 in the indexing ring 58 so as tolock the indexing ring 58 and prevent rotation thereof.

A tube 69 fitted into the open end of the nipple 66 (Figs. 4 and 5)extends rearwardly and terminates at one of the handle bars 35 asindicated in Fig. 2 and is fixed to this handle bar by some suitableclamp 10. Mounted in this tube 69 is a flexible cable H that is adaptedat one end (Fig. 4) to the lower end of the shank 54 of the indexing pin62. The other end of this flexible cable H projects out through theopposite end of the tube 69 (Fig. 2) and is provided with a hand graspknob 12 that is readily accessible to the person operating the saw whilehe is positioned behind the handle bars 35. By the exertion of a pull onthe hand grasp knob 12 (Fig. 2), which force is transmitted throughflexible cou ling ll to the indexing pin 62, the tooth or lug 68 iswithdrawn from the slot in the indexing ring 58 so that the entire tube31 (Fig. 5) together with the cutter assembly unit 38 can rotate freelyabout the tube I8 until the desired position for the saw blade 54 hasbeen effected, and then upon releasing the knob 12, the indexing pin 62is again forced upwardly by the action of compression spring 61 to causethe tooth or lug 68 on the indexing pin 62 to enter the correspondingslot 59 in the indexing ring 58. The position of the saw blade is againlocked and the saw is ready for use with the blade in its new position.

All of this can be accomplished while the operator of the saw unit ispositioned behind the handle bars 35. The rotation of the saw blade toits new position is brought about by tilting the entire unit forwardlyuntil the saw blade end of the machine engages the ground and then theentire saw unit is turned to the left or the right with respect to theperson behind the handle bars while maintaining the saw blade end on theground and while further tilting the saw unit forwardly until thedesired angle has been reached by the saw blade. While the machine isthus held the indexing pin is returned to its locking position and thesaw is then ready for use.

In Fig. 3 the saw blade 54 is shown in engagement with the ground in thebroken line position illustrated at 540. and by manipulation of theentire saw unit in the manner just described, this blade can be moved bycooperation of the ground to the vertical position illustrated in thisfigure or to any other desired positions where it can be locked.

Referring to Fig. 8 the portable saw is shown on the side of a hill 15in position to cut down a tree illustrated at 16. In this instance it isnoted that in spite of the fact that the supporting wheels of the saware disposed at different elevations the saw blade 54 is nevertheless inposition to make a horizontal cut through the trunk of the tree. Thisposition of the saw blade is brought about by proper indexing of thetube 31.

When it is desired to make a shallow out, as for example, when notchinga tree, a mere nudge of the machine into the tree is all that isrequired. A belt Tl fastened across the ends of the handle bars 35 asbest shown in Fig. 2 is of particular advantage in such an instance. Theoperator of the machine can urge the machine forward with his bodydisposed against this belt. This is particularly desirable for notchinga tree where only a shallow feed of the saw is required because of theresiliency afforded by the belt. This resiliency also reduces vibrationsand shocks for the operator during normal operation of the saw if heapplies the required pushing force with his body through the belt.

It is to be noted that the indexing sleeve assembly 51 is rigidly fixedwith respect to the engine 23. This makes for sturdiness in the construction and operation of this assembly. The position of the saw blade54 can easily and quickly be adjusted and locked independently of theposition of the wheels l2. This is demonstrated by the two positionsshown in Figs. 1 and 8 respectively where the wheels are disposedhorizontally and at an inclination respectively, though in each instancethe saw blade 54 is shown in a horizontal plane.

Referring to Fig. 1 the blade 54, even in its lowest position, is abovethe lowermost position of the wheels l2. Thus the saw may be wheeledover even rough ground without danger of striking the blade against theground. To give additional clearance the blade 54 may be indexed to somehigher position, such as that shown in Fig. 2 in broken lines.

I claim:

1. A saw comprising a wheeled support struoture having a sleeve mountedthereon, a first tubular member telescoped inside said sleeve, securedthereto and extending rearwardly therefrom, said sleeve having a forwardend portion of enlarged bore cooperating with said first tubular memberto define an annular recess, a second tubular member extending forwardlyfrom said sleeve and having one end journalled in said recess, anindexing ring secured to said second tubular member adjacent saidsleeve, a clamping ring disposed over said indexing ring and secured tosaid sleeve to hold said second tubular member in position in saidrecess, a saw blade operatively 6 mounted on the free end of said secondtubular member, and means for rotating said blade.

2. A saw comprising a wheeled support structure, a first arm extendingrearwardly from said support structure, a prime mover mounted on saidfirst arm, a second arm journalled for rotation at one end in saidstructure and extending forwardly therefrom, a saw rotatably mounted onthe free end of said second arm, drive means connecting said prime moverto said saw, a releasable locking means connected between said secondarm and said support structure including an indexing ring secured tosaid second arm, and a clamping ring secured to said support structureand engaging said indexing ring to hold said second arm in position onsaid support structure.

3. In a portable power unit, the combination which comprises a hollowtubular frame mounted on wheels, an engine carried by said frame,handles operably connected to said frame, said frame having a forwardlyextended section mounted for turning movement relative to remainder ofsaid frame, a tool holding arbor carried by the outer end of saidforwardly extended frame section, an index plate having spaced openingstherein and mounted to be enclosed within said tubular frame, a springactuated pin positioned to engage said index plate openings for securingsaid forwardly extended section and tool holding arbor in adjustedpositions, means for forcing said spring actuated pin out of said indexplate openings for turning said shaft and arbor, and drive shaft meansextending within said hollow tubular frame for driving the arbor fromthe engine.

4. In a portable circle power saw unit, the combination which comprisesa hollow frame mounted on wheels, an engine carried by said frame,handles operably connected to said frame, a forwardly extended hollowtubular member aligned with said hollow frame and mounted for turningmovement on said frame, a tool holding arbor carried by the outer end ofsaid tubular member, an index plate having spaced openings therein andmounted on said tubular member and enclosed therein, a spring actuatedpin positioned to engage the said index plate openings for securing saidtubular member and said tool holding arbor in adjusted positions, meansfor forcing said spring actuated pin out of said index plate openingsfor turning the said shaft and arbor, and means for extending withinsaid hollow frame and said tubular member for driving said arbor fromsaid engine.

ARTHUR W. MALL.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 752,763 Donavin et a1 Feb. 23, 1904 910,145 OI-Iara Jan. 19,1909 1,513,469 Robinson Oct. 28, 1924 1,696,527 Crumly Dec. 25, 19281,858,015 Hodgson May 10, 1932 2,407,028 McLean Sept. 3, 1946 2,412,704Jaques Dec. 1'7, 1946 2,435,192 Arsneau Feb. 3, 1948 2,477,677 WoodlingAug. 2, 1949 2,509,090 Faccon May 23, 1950 FOREIGN PATENTS NumberCountry Date 188,674 Great Britain Apr. 12, 1923 255,007 Great BritainJuly 15, 1926 115,148 Australia May 12, 1942

